Clark is located in west Pennsylvania. Clark is part of Mercer County. Clark has 3.01 square miles of land area and 0.61 square miles of water area. As of 2010-2014, the total Clark population is 629, which has shrunk 0.63% since 2000. The population growth rate is lower than the state average rate of 3.89% and is much lower than the national average rate of 11.61%. Clark median household income is $69,250 in 2010-2014 and has grown by 29.59% since 2000. The income growth rate is lower than the state average rate of 32.44% and is higher than the national average rate of 27.36%. Clark median house value is $164,400 in 2010-2014 and has grown by 71.61% since 2000. The house value growth rate is about the same as the state average rate of 70.00% and is much higher than the national average rate of 46.91%. As a reference, the national Consumer Price Index (CPI) inflation rate for the same period is 26.63%. On average, the public school district that covers Clark is better than the state average in quality. The Clark area code is 724.